The present invention relates to a pushbutton assembly, and more particularly to a pushbutton assembly having a positioning rod rotatably connected to a button and a positioning disk pivotally received in a housing of the pushbutton assembly and having a positioning hole defined in the positioning disk to receive therein a bent of the positioning rod such that repeated up and down movement of the button allows the bent to be positioned at a first position and a second position within the positioning hole to accomplish the designed purpose of the pushbutton assembly.
U.S. Pat. Nos. 4,167,720; 4,937,548; 5,233,813; 5,451,729; 5,558,211 are numerous patents related to a pushbutton assembly, which all suffer from the following shortcomings:
Too many linking parts are involved in a single movement, which causes a complex process to accomplish a single purpose and a non-real-time action; and
Because the quantity of the parts to accomplish a single action is large, possibility of malfunction is great and the quality of communication between parts is low.
With reference to FIG. 1, a conventional pushbutton assembly is shown to have a button (601) and a housing (606).
The button (601) is mounted on top of a body (not numbered) having a V-shaped protrusion (603) which is formed on a bottom of a channel (602) and has a lowermost point (a). The channel (602) has a lowermost point (b). A positioning rod (604) has a first end inserted into the through hole (607) in the housing (606) and a second end (605) extending into the channel (602). A spring (608) is employed to provide a resilience to the button (601) and to ensure that the second end of the positioning rod (604) to abut an inner face of the channel (602).
When the user presses the button (601), the second end of the positioning rod (604) moves from point (a) to point (b). When the user pushes the button (601) again, the second end of the positioning rod (604) moves from point (b) to point (a). When the pushbutton assembly is used for a period of time, the resilience of the spring (608) is deteriorated, the engagement of the second end (605) of the positioning rod (604) with the inner face of the channel (602) is not secured. Therefore, it is noted that the second end (605) of the positioning rod (604) may deviate from point (a) if the resilience from the spring (608) is not enough. Another shortcoming from the insufficient resilience is that the contact (610) of the electrical plate (609) may not engage with the contact (612) of the pin (611) properly and thus causes malfunction.
Accordingly, the conventional pushbutton assembly uses too many parts so that the cost is high and the possibility of having malfunction is thus high.
In order to obviate the shortcoming described in FIG. 1, U.S. Pat. No. 5,223,813 discloses an indirect contact between the button and the resilient plate. This indirect engagement between the button and the resilient plate does provide improvements over the prior art. However, there are too many parts involved in the structure and thus manufacture cost is high and the drawback of metal fatigue still bothers the operator.
To overcome the shortcomings, the present invention tends to provide an improved pushbutton assembly to mitigate and obviate the aforementioned problems.
The primary objective of the present invention is to provide an improved pushbutton assembly having a positioning rod rotatably connected to a button and a positioning disk pivotally received in a housing of the pushbutton assembly and having a positioning hole defined in the positioning disk to receive therein a bent of the positioning rod such that repeated up and down movement of the button allows the bent to be positioned at a first position and a second position within the positioning hole to accomplish the designed purpose of ON/OFF function of a resilient plate of the pushbutton assembly.